SpeakerTalk

[KefHeir]

I was wondering if anyone here had any insights or experience of how to get the best performance from Kef speakers at low volume? I have a pair of homemade Kef 3 ways based on the Concerto design (which you can just about see in my profile picture). I've just replaced all the drivers with new ones from Falcon Acoustics. At medium to high volumes they sound fantastic but unfortunately I have to do a lot of listening at low volume and I find below a certain level there seems to be quite a steep drop off in the mid range relative to the higher frequencies. I presume this is largely to do with mechanical resistance being relatively more significant at lower volume levels, and I know there is science on human hearing being less sensitive at low volumes, so I'm just wondering if there's anything which can make an incremental improvement?

I know that the Kef drivers are not that sensitive, so will a power amp with more grunt help things (more is better seems to be the general rule with amplification)? Elsewhere I recall reading that it's amplifier topology and 'the first watt' which is more important than power as such.

I'm currently running a passive pre-amp with a NAIM NAP 100 (50w). I'm pretty certain the NAIM is under-powered for these speakers so I need something with more oomph, but would appreciate any insights on this low volume question.

(I searched the forum for a related thread but couldn't see anything, but if you know of one I'd be grateful for a signpost.)

Thanks, and hope everyone is finding ways to survive the pandemic

[speakerguru]

Not what you want to hear, but you'd be better off using headphones.

[audiolabtower]

Amplifiers used to have a loudness control for this very reason. Unfortunately they worked the other way round, boosting bass and treble since human hearing subjectively will hear the mid range more at low volumes. If you could borrow another amp it might be worthwhile since some old Naim amps had a resistor in the output which may interact with the speaker impedance at low output, but I am a little doubtful for a large effect. Guru's idea is the best, or an inexpensive small bookshelf speaker at and near ear level just for low level listening.

[KefHeir]

Thanks @speakerguru and @Audiolabtower for the thoughts on this. Couple of things to try even if only marginal gains

[speakerguru]

I exclusively use a pair of Model 101s and a pair of Chartwell LS3/5As for low level mixing and monitoring atm. I'm at about a distance of 0.5m away. No complaints from my wife or neighbours so far .

[KefHeir]

@Speakerguru - either of those would be more appropriate for my small space I daresay, but I've inherited these big 3 way units so trying to make them work. The new drivers are all kinds of better but just have this impression there's something odd going on with the dynamic range which stretches from slightly too loud to the hard to hear on some concerto and piano music, which is largely what I listen to.

I wondered if anyone knows a really good / useful acoustic test CD I could try?

[speakerguru]

[KefHeir]

@speakerguru - I think the ears are OK, or at least I hope so - I've led a fairly quiet life in both senses Might just be a period of adjustment is needed to acclimatise to the new drivers. The others were 40 years old so it's a dramatic change

I did wonder though, does anyone offer speaker testing as a service outside of the professional industry? It would be good to get a more objective sense of the performance now I've embarked on this improvement journey.

On another topic, along with the speakers themselves I also inherited some paperwork including Kef enclosure designs & blueprints; a short pamphlet by someone called Siegfried Linkwitz who appears to have had some association with Kef (?); etc. Are those of interest on this forum?